// Copyright (C) 2005, 2006 International Business Machines and others.
// All Rights Reserved.
// This code is published under the Eclipse Public License.
//
// Authors:  Andreas Waechter              IBM    2005-10-127

#ifndef __LUKSANVLCEK4_HPP__
#define __LUKSANVLCEK4_HPP__

#include "RegisteredTNLP.hpp"

using namespace Ipopt;

/** Implementation of Example 5.4 from "Sparse and Partially Separable
 *  Test Problems for Unconstrained and Equality Constrained
 *  Optimization" by L. Luksan and J. Vlcek.
 */
class LuksanVlcek4: public RegisteredTNLP
{
public:
   /** Constructor.
    *
    *  Here, g_l and g_u are the bounds for the
    *  constraints.  The original formulation is obtained by setting
    *  g_l and g_u to zero.  Using g_l<g_u allows the obtain a problem
    *  formulation with inequality constraints.
    */
   LuksanVlcek4(
      Number g_l,
      Number g_u
   );

   /** Default destructor */
   virtual ~LuksanVlcek4()
   { }

   // overloaded from RegisteredTNLP.
   virtual bool InitializeProblem(
      Index N
   );

   /**@name Overloaded from TNLP */
   //@{
   /** Method to return some info about the nlp */
   virtual bool get_nlp_info(
      Index&          n,
      Index&          m,
      Index&          nnz_jac_g,
      Index&          nnz_h_lag,
      IndexStyleEnum& index_style
   );

   /** Method to return the bounds for my problem */
   virtual bool get_bounds_info(
      Index   n,
      Number* x_l,
      Number* x_u,
      Index   m,
      Number* g_l,
      Number* g_u
   );

   /** Method to return the starting point for the algorithm */
   virtual bool get_starting_point(
      Index   n,
      bool    init_x,
      Number* x,
      bool    init_z,
      Number* z_L,
      Number* z_U,
      Index   m,
      bool    init_lambda,
      Number* lambda
   );

   /** Method to return the objective value */
   virtual bool eval_f(
      Index         n,
      const Number* x,
      bool          new_x,
      Number&       obj_value
   );

   /** Method to return the gradient of the objective */
   virtual bool eval_grad_f(
      Index         n,
      const Number* x,
      bool          new_x,
      Number*       grad_f
   );

   /** Method to return the constraint residuals */
   virtual bool eval_g(
      Index         n,
      const Number* x,
      bool          new_x,
      Index         m,
      Number*       g
   );

   /** Method to return:
    *   1) The structure of the Jacobian (if "values" is NULL)
    *   2) The values of the Jacobian (if "values" is not NULL)
    */
   virtual bool eval_jac_g(
      Index         n,
      const Number* x,
      bool          new_x,
      Index         m,
      Index         nele_jac,
      Index*        iRow,
      Index*        jCol,
      Number*       values
   );

   /** Method to return:
    *   1) The structure of the Hessian of the Lagrangian (if "values" is NULL)
    *   2) The values of the Hessian of the Lagrangian (if "values" is not NULL)
    */
   virtual bool eval_h(
      Index         n,
      const Number* x,
      bool          new_x,
      Number        obj_factor,
      Index         m,
      const Number* lambda,
      bool          new_lambda,
      Index         nele_hess,
      Index*        iRow,
      Index*        jCol,
      Number*       values
   );

   /** This method is called when the algorithm is complete so the TNLP can store/write the solution */
   virtual void finalize_solution(
      SolverReturn               status,
      Index                      n,
      const Number*              x,
      const Number*              z_L,
      const Number*              z_U,
      Index                      m,
      const Number*              g,
      const Number*              lambda,
      Number                     obj_value,
      const IpoptData*           ip_data,
      IpoptCalculatedQuantities* ip_cq
   );
   //@}

private:
   /**@name Methods to block default compiler methods.
    *
    * The compiler automatically generates the following three methods.
    *  Since the default compiler implementation is generally not what
    *  you want (for all but the most simple classes), we usually
    *  put the declarations of these methods in the private section
    *  and never implement them. This prevents the compiler from
    *  implementing an incorrect "default" behavior without us
    *  knowing. (See Scott Meyers book, "Effective C++")
    */
   //@{
   LuksanVlcek4();

   LuksanVlcek4(
      const LuksanVlcek4&
   );

   LuksanVlcek4& operator=(
      const LuksanVlcek4&
   );
   //@}

   /** Parameter determining problem size */
   Index N_;

   /** General lower bound for all constraints */
   Number g_l_;
   /** General upper bound for all constraints */
   Number g_u_;
};

#endif
